Here is the symptom chart for no forward gears.
Possible Component Reference/Action
201 — ELECTRICAL ROUTINE
No Electrical Concerns
301 — HYDRAULIC/MECHANICAL ROUTINE
Fluid
Improper level
Adjust to proper level.
Shift Linkage (Internal/External)
Transmission shift cable and bracket damaged or misadjusted. TR sensor out of adjustment
Inspect for damage. Readjust as required. Service all damaged components. After servicing linkage, readjust TR sensor.
Improper Pressures
Improper band/clutch application pressure, line pressure low
Check line pressure at tap. Perform line pressure and stall speed tests. Refer to pressure chart No. 401 for specifications. If pressure is low, check the following possible components: main control, filter/seal, pump assembly.
Filter and Seal Assembly
Filter damaged, plugged; seal damaged, cut or missing
Inspect for damage and replace.
Main Control Assembly
Screw out of torque specification
Tighten to specification.
Gaskets damaged, off location
Inspect and replace gasket.
Separator plate damaged
Inspect for damage. Service as required.
Forward modulator valve/EPC boost valve (207), forward engagement control valve (209), spring, damaged, missing, misassembled, stuck, bore damaged
Inspect for damage. If damaged, replace main control. If parts are missing, replace missing parts or main control. If misassembled, reassemble properly. Do not stone, file or sand valves. This will remove the anodized finish and may result in further main control or transmission damage.
Wrong component used in rebuild
Verify that proper components were used.
Pump Assembly
Pump damaged, leaking
Inspect for damage. Service or replace as required.
Screws out of torque specification
Tighten screws to specification.
Center Support Assembly
Forward clutch support seal rings leaking
Perform air pressure check. If OK, go to forward clutch assembly. Service as required.
Forward Clutch Assembly
Forward clutch assembly burnt/damaged/leaking. Check ball in cylinder/leaking piston seal rings
Perform air pressure check. Service as required.
Rear One-Way Clutch Assembly
Rear one-way clutch damaged, worn
Replace rear one-way clutch and case.